Water-tube boiler



Oct. 25 1927.

C. `L. ROSZAK WATER TUBE BOILER Filed July 21, 1927 4 Sheets-Sheet l Fl G.. 6.

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1,646,933 OC- 25 1927 c. L. RoszAK WATER TUBE BOILER Filed July 2l, 1927 4 Sheelzs-Shee'rl 2 @vow www l 1646,933 oct. 25,1927. y C'LROSZAK ,Y

WATER TUBE BOILER Filed July 21, 1927 l 4 Shesscs-Sheei'l 3 1 646,933 oct. 25,1927. C. L ROSZAK WATER TUBE BOILER Filed July 2L 1927 4 Sheets-Sheet 4 Patented Oct. 25, 1927.

I UNITED STATES CHARLES LOUIS ROSZAK,

F PARIS, FRANCE, ASSIGNOR TO THE BABCOCK &: WILCOX COMPANY, OF NEW YORK, N. Y.

WATERTUBE BOILER.

Application led July 21, 1927, Serial No. 207,517, and in France July 19, 1926.

The resent invention relates to a watertube boiler of the substantially vertical tube type red with fuels such as pulv'erized coal, gases or liquids.

6 In existing boilers of this type, and particularly boilers tired with 'pulverized fuel, the fiame passes into a huge combustion chamber of parallelepiped form and 1mmediately expands, thus considerably dimm- 10 ishing the speed of fiow of the gases. As the rate of heat transference falls with the fall in speed of the heating medium, 1t 1s an advantage to have a combustion chamber shaped to conform with the flame so as to maintain the speed of flow of the gases.

The present invention provides an 1mproved form of combustion chamber the walls of which' are formed by water tubes disposed to limit the expansion of the combustion gases, while reservin their direction and speed, the ame having a vertical axis and bein directed upwardly whether there is a sing e jet or row of jets or a pair of convergent jets or rows of jets.

The advantages ofthis arrangement may be summarized as follows:

The zone of maximum temperature is disposed towards the upper ends of the tubes; The generation of steam will take place mainly towards the upper ends of the tubes, in the region of maximum temperature. The distance through which the bubbles of steam will fiow from their starting pointto the water level in the upper drum will be very short and consequentl the steam passing into the said drum wi l be particularly dry; since there are rows of tubes on opposite sides of the flame issulng from the burners substantially the entire heat radlated by the flame will 'be absorbed by the direct surface.

The ash-containing dust which Lmay fuse in the flame will be solidified by the cold walls and will a ain become pulverulent 1 n the gases and wi not agglomerate; the. d1-

rect heating surface of the boiler will thus act as a water-screen;

The combustion chamber being of rational shape, since it takes the form of the-flame,

5 does not require to be abnormally high;

4The return iiow of the gases downwardly towards the flue or iiues ensures the deposit of the ashes in two large ash chambers situated at the lower end of the boiler, whence they may be removed by suitable appliances;

The accumulation of soot will be avoided, as the lower drums are free at both sides and the tubes are nearly vertical;

It is to be noted that the fuel-laden air jet issuing from the burner is delivered at a high speed suiicient for the suspension of the particles of coal in the air. This speed isv suflicient to ensure that the ame will reach the upper end of the boiler.

The invention will be understood from the description in connection with the ac companying drawings. In the drawings Figs. l, 2, 3 and 4 are vertical sections through illustrative embodiments of the invention, partly diagrammatic; Fig. 5 is a. diagrammatic endview showing the general arrangement of an illustrative embodiment of the invention; and Fig. 6 is a side view corresponding to Fig. 5.

The same reference characters indicate like parts in the different figures of the drawings. A

In the drawings, reference 'character R in-V dicates an upper steam and water drum that is connected to lower water drums r and r by banks of vertically disposed tubes T and T. The tubes T and T are so shaped and spaced that they bound a combustion chamber having in cross section a generally pearshaped outline that conforms to the outline of a free flame passing vertically upwards from a row of fuel burners B. The space between the inner rows of tubes of each bank of tubes T and T is divided into an upper chamber D and a lower chamber D connected by a restricted passage E as most clearly shown in Figs. 2 and 3. The fuel burners B are located in the lower chamber D. Substantially vertical baiiles C and C' are located on opposite sides of the pea-'rshaped combustion chamber and may be so located that a portion of each bank of tubes is' on opposite sides of the ballles as indicated in Figs. 1, 2 and 3, or the bafes C and C may be so located that all of the tubes T and T are outside of the same as indicated in Figs. 4 and 5. The flame and gases entering through the burners B pass upwardly as indicated by the arrows, thence over the top edges of the baiiiesC and C and downwardly between these bailies and the outer wallsof the boiler and through openings o and o into an outlet flue P.

AOpenings o and o may also be provided in the lower portions of the outer walls of the boiler to permit waste gases to pass therethrough. Downcomer tubes represented by the dotted lines p and in Figs. 1, 2 and 5, and by solid lines in Figs. 3 and 6, may be located outside of the boiler walls and connect the upper drum R to the lower drums 7' and r. Ash pits d and d are located on opposite sides at the bottom, in which ash pitsv dust soot or ashes -may collect and be removed in the usual way.

lny the modification shown in Fig. 2, the products of combustion after passing downwardly on the outside of the balies C and C', ythen pass upwardly through iues in which economizers E and E are located, these iiues extending upwardly between the combustion chamber and the outer walls of the boiler. In this modification, superheaters S and S are shownin the space above the baffles C and C and air heaters A and A are shown below the drums r and r composed of tubes lying along the inside wall of the ash pits d and ai.

In the modiication shown in Fig. 3, thev openings o and o for the products of comnl bustion are disposed in a manner similar to that shown in Fig. l, and the superheaters E and E are located in the lower portion of the boiler setting so that the products of combustion pass over the superheater tubes just before they enter the outlets o and 0.

The modification shown in Fig. 4 is somewhat similar to that shown in Fig. 2, but in this modiiication the bales C and C lie entirely within the bank of tubes T and T.

In the diagrammatic illustration of Fig. 5, the path of the products of combustion is indicated by the arrows all the way to the stack in an embodiment in which the economizers are located in iues on opposite sides of the boiler; and Fig. 6 is a side view in which the arrangement of the row of burners B is more clearly indicated in dotted lines.

'Ihe tunnel X from which the burners project-may serve for housing the necessary ap paratus and motors, thus saving boiler space.

I claim 1. In a water tube boiler, an upper drum, a plurality of spaced lower drums, banks of tubes connecting said upper drum to said lower drums, and forming a combustion space therebetween, the innermost row of tubes on opposite sides of said combustion space having the lower portion bent towards 'each other to a distance less than the distance between said lower drums to form a constricted passage, and an upper portion bent away from each other, and a burner` located below the point where said tubes approach each other nearest.

2. In a water tube boiler, an upper drum, a plurality of spaced lower drums, banks of tubes connecting said upper drum to said lower drums, the inner row of tubes of each of said banks being bent inwardly at their upper ends and at an intermediate point to form in conjunction with said drums, cham bers that are connected by a narrow passa e, the upper chamber decreasing in size at oth ends thereof, and means to cause hot products of combustion to pass downwardly along the outer tubes of said banks.

In testimony whereof I have signed my name to this speciication.

QHARLES LOUIS ROSZAK. 

